Controlling apparatus for highway crossing signals



Patented Aug. 10, 1937 UNETED STATES PATENT OYFFIQE CONTROLLING APPARATUS FOR HIGHWAY CROSSING SIGNALS Application November 3, 1936, Serial No. 108,988

11 Claims.

My invention. relates to controlling apparatus for highway crossing signals, that is, to apparatus for the control of signals which are placed at the intersections of. railways and highways for the purpose of warning users of the highway when a train is. approaching.

I will describe two forms of apparatus embodying my invention, and will then point out the novel features thereof in claims.

Fig. 1 of the accompanying drawing is a diagrammatic view illustrating one form of apparatus embodying my invention, as applied to a stretch of track over which traffic moves in both directions- Fig. 2 is a diagrammatic view illustrating a modification of a portion of the apparatus shown in Fig. 1, and also embodying my invention.

Similar reference characters refer to similar parts in each of the several views.

Referring first to Fig. 1, the reference characters 3and 4 designate the rails of a stretch of track over which trafiic normally moves in both directions. The stretch is divided by insulated joints 5 into two adjacent track sections, designated by the reference characters IT and 2T, respectively. Each track section is provided'with a track circuit including a track battery 6 connected across the rails at one end of the section and with a track relay, designated by the reference character M with a prefix the same as the prefix in the reference character of the associated section, connected across the rails at the other end of the section. As here shown, the relays ME and M2 are the magnets of an interlocking relay K. At the junction of the two sections, the stretch of track is intersected by a highway H. The highway H is protected by a signal, designated in general by the reference character S, and capable of displaying a green light to indicate proceed, a yellow light to indicate cauti'on, and a red light toindicate stop.

As here shown, the signal S includes an armature l? mounted to rotate between an intermediate position; to which it is biased, and two extremepositions; The armature l is controlled by an armature 'winding'8 and is polarized by the field of apermanent magnet or an electromagnet (not shown) in such a manner that, when winding 8'isenergized; armature i will rotate to its left-hand or right-hand extreme position according as winding 8- is supplied with current of normal or reverse polarity, respectively. Attached to armature l to rotate therewith are roundel's G, R and Y, which are arranged to be disposed-inthe path of a'beam of light projected from a lamp E according. as armature 1 occupies its left-hand extreme position, itsintermediate. position or its right-hand extreme position, respectively. The roundels G, R and Y cause the signal to display a green or a red or a yellow light, respectively, according to the position of armature l." Operably connected to armature I is a circuit controller comprising two movable contact fingers 9 and 10. Contact finger: 9 cooperates with a fixed contact II to close a con? tact 9-I I when armature, l occupies its left-hand extreme position, and contact iflcooperates with a fixed contact l2 to close a'contact lfi'l2'when armature I occupies its right-hand extreme position. A signal of thetypedescribed is disclosed and claimed in'Letters Patent of the UnitedStates No. 1,864,224, granted to Wesley B. Wells, on June 21, 1932, for Light signals.

The reference character TE designates a timing device which is here shown as a relay having a slow releasing characteristic and which, as will be explained more in detail hereinafter, is provided for causing the signal to display the stop indication a predetermined time interval after the caution indication has been displayed.

With both sections iT and 2T unoccupied, that is, with all apparatus in its normal condition as shown in the drawing, winding 8 is energized in the normal direction, and both lamp E and relay TE are energized so that the signal S is caused to display a green light to indicate proceed. The circuit for winding 8 may be traced from terminal B of any suitable source of energy through front point of contact is of magnet M2, front point of contact M of magnet M2, front contact I5 of relay TE, winding 8, front contact l6 of relay TE, front point of contact ll of magnet MI, andfront point of contact I8 of magnet M2 to terminal C of the source of energy. The circuit for lamp'E may be traced from terminal B over front contacts'l9 and 20 of magnets M2 and MI, respectively,.contact 9H of signal S, and lamp E to terminal C. The circuit for relay TE may be traced from terminal B over front contact I9 of magnet M2, front contact 20 of magnet MI and relay TE to terminal C.

I shall assumethat an eastbound train; that is, a train traveling from left to right, enters section IT so that magnet Ml becomes released. The releasing of magnet Ml; will supply current of reverse polarity over backpoints of contacts l4 and ll of magnet Ml to winding 8 so that signal S will be caused-to assume its right-hand extreme position to display a yellow light to indicate caution and the operation of relay TE attains its right-hand extreme position. Consequently, the lamp E is extinguished during the time armature 1 is passing through its intermediate position so that a momentary display of the red light is avoided. 1 a

When relay TE completes its operation, front contacts l6 and I! will be opened so that winding 8 will become deenergized to causesignal S to display the red light to indicate stop. The

circuit for the lamp E, at this time, includes back contact 22 of relay TE. I When the train vacates section IT and enters 2T, magnet MI will be restored to its energized condition and, although magnet M2 will become deenergized, the interlocking feature of the relay will prevent the opening of the front contacts or the closing of the back contacts of magnet Ml so that the signal S, lamp E and relay TE will again be caused to assume their normal condition. Consequently, signal S will again display the green light to indicate proceed.

From .the foregoing description of the operation of the apparatus shown in. Fig. 1, it will be,

apparent that normally a proceed? indication will be displayed, and that, upon'the approach of a train, a caution indication will be displayed until the lapse of a predetermined time interval when a stop indication will be displayed which will continue until the train clears the highway intersection.

The apparatus operates in a similar manner for a westbound train and it is believed, therefore, unnecessary to givea detailed description of a westbound movement. AlthoughI have shown and described the apparatusherein as being applied to a stretch of track overwhich traflic normally moves in both directipns, it will be understood that, by substituting an ordinary track relay for the magnets of the interlocking relay, my invention may be applied to a stretch of track over whichtraffic normally moves in one direction only.

Referring now to Fig. 2, the apparatus shown herein differs from that shownin Fig. 1, only in that the timing device TE is here shown as a normally deenergized relay having a slow pickup characteristic. That is, when either magnet Ml or M2 becomes released to close either back contact 2! or back contact 22, relay TE will be .come energized so that, when relay TE completes its operation, backcontacts 23 and 24 will become opened to cause the signal S to display the stop indication. The circuit for lamp E, when the apparatus is in condition to display the stop indication, includes front contact 25 of relay TE. Otherwise, the apparatus shownin Fig. 2 operates in a manner similar to' that just described 'for the arrangement shown in'Fig. 1, and it is believed, therefore, that the operation of the apparatus shown in Fig. 2-will be entirely clear without detailed additional explanation. 1 "Although I have herein shown and described only two forms of apparatus embodying my inventi'on, it is understood that various changes and modifications may be made therein Within the scope of the appended claims without departing from the spirit and scope of my invention.

Having thus described my invention, what I claim is:

1. In combination, a stretch of railway track including an intersection with a highway, a track section which will be occupied by a train approaching said intersection, a track circuit for said section including a track relay, a highway crossing signal capable of displaying a proceed and a caution as well as a stop indication according as the signal is energized in one direction or in the other direction or deenergized respectively, means governed by said track relay for reversibly governing said signal, a timing device effective at times to deenergize said signal, and means controlled by said track relay for governing said timing device.

2. In combination, a stretch of railway track including an intersection with a'highway, a track section which will be occupied by a train approaching said intersection, a track circuitfor said section including a track relay, a highway crossing signal capable of displaying a proceed and a caution as well as a' stop indication according as the signal is energized in one direc- 7 tion or in the other direction or deenergized re,

spectively, a timing device having an initial condition and an operated condition, means governed by said track relay for supplying said signal with current in said one direction or in said other direction according as the track relay is picked up or released respectively efiective if and only if .said timing device is in its initial condition, and means effective for initiating the operation of said timing device when said track relay is released.

3. In combination, a stretch of railway track including an intersection with a highway, a track section which will be occupied by a train approaching said intersection, a track circuit for said section including a track re1ay,,a highway crossing signal capable of displaying a proceed and a caution as well as a stop indication according as the signal is energized in one direction or in the other direction or deenergized respectively, a normally energized timing device having an initial condition and an operated condition, means governed by said track relay forsupplying said signal with current in said one direction or in said other direction according as the track relay is picked up or released respectively effective if and only if said timing device is in its initial condition, and means eifective to deenergize said timing device to initiate its operation when said track relay is released.

4. In combination, a stretch of railway track including an intersection 'with a highway, a track section, which Will be occupied by a train approaching said intersection, a track circuit for said section including aitrack' relay, a highway crossing signal capable of displaying a proceed and a caution as well as a stop indication according as the signal is energized in onedirection or in the other direction or deenergized respectively, a normally deenergized timing device having'an initial condition and an operated condition, means governed by said track relay for supplying said signal with current in said one direction or in said other direction according as the track relay is picked up or released respectively effective if and only if said timing device is in its initial condition,'and means effective to energize said timing device to initiate its operation when said track relay is released.

5. In combination, a stretch of railway track including an intersection with a highway, a track section which will be occupied by a train approaching said intersection, a track circuit for said section including a track relay, a highway crossing signal capable of displaying a proceed and a caution as well as a stop indication according as the signal is energized in one direction or in the other direction or deenergized respectively, a circuit for supplying said signal with current in said one direction including a pair of front contacts of said track relay, a circuit for supplying said signal with current in said other direction including a pair of back contacts of said track relay, and means effective a predetermined time interval after said track relay is released to deenergize said signal.

6. In combination, a stretch of railway track including an intersection with a highway and a track section extending in one direction from said intersection, a highway crossing signal for said intersection capable of displaying a proceed and a caution as well as a stop indication according as said signal is energized in the normal direction or the reverse direction or deenergized respectively, a timing device having an initial condition and an operated condition, means effective only when said timing device is in its initial condition to supply said signal with current of normal polarity or reverse polarity according as said section is occupied or unoccupied respectively, and means efiective to initiate the operation of said timing device when said section becomes occupied.

7. In combination, a stretch of railway track intersected by a highway and including two track sections one extending in each direction from said highway, a track circuit for each section including a track relay, a highway crossing signal capable of displaying a proceed and a caution as well as a stop indication according as it is energized in one direction or in the other direction or deenergized respectively, means for supplying said signal with current in one direction when both relays are picked up and for supplying said signal with the current in the other direction when either relay is released, and other means effective to deenergize said signal a predetermined time interval after the signal is supplied with current in said other direction.

3. In combination, a stretch of railway track intersected by a highway and including two track sections one extending in each direction from said highway, an interlocking relay including a first magnet and a second magnet controlled by trafilc conditions in said two sections respectively,

a highway crossing signal capable of displaying a proceed and a caution as well as a stop indication according as it is energized in one direction or in the other direction or deenergized respectively, means for supplying said signal with current in said one direction when both magnets are picked up and for supplying said signal with current in said other direction when either magnet is released, and other means controlled by said two magnets for deenergizing said signal a predetermined time interval after either magnet is released.

9. In combination, a stretch of railway track intersected by a highway and including two track sections one extending in each direction from said highway, an interlocking relay controlled by traific conditions in said two sections, a threeindication highway crossing signal responsive to the polarity of the current supplied thereto, means governed by said interlocking relay for reversibly governing said signal to provide proceed and caution indications, and other means governed by said interlocking relay for causing the signal to display a stop indication a predetermined time interval after the display of the caution indication.

10. In combination, a stretch of railway track intersected by a highway and including two track sections one extending in each direction from said highway, a highway crossing signal at said intersection including a mechanism and a lamp cooperating therewith to provide three indications according as the mechanism is supplied with current in one direction or the other direction or is deenergized respectively, an interlocking relay controlled by trafiic conditions in said two sections for reversibly governing said signal, a timing device governed by said interlocking relay for deenergizing said signal, and means governed by said interlocking relay and by said timing-device for governing said lamp.

11. In combination, a stretch of railway track intersected by a highway and including two track sections one extending in each direction from said highway, a highway crossing signal at said intersection including a mechanism and a lamp cooperating therewith to provide three indications according as the mechanism is supplied with current in one direction or the other direction or is deenergized respectively, an interlocking relay controlled by trafilc conditions in said two sections for reversibly governing said signal, a timing device governed by said interlocking relay for deenergizing said signal, and traffic controlled means including contacts operably governed by the signal for controlling said lamp.

GEORGE R. PFLASTERER. 

